This proposal links STD-related basic, clinical and behavioral-outreach components so that a meaningful and interactive network of projects and cores is established in South Texas and coordinated with similar efforts throughout the United States and elsewhere. The control of STD transmission requires a fundamental understanding of the virulence properties of specific etiological agents, their mode of transmission and the biological and social dynamics of the at-risk population. In addition, a lay and professional educational effort that outlines diagnosis, prevention and treatment compliance is essential. Our goal is to utilize several qualities of the San Antonio community to provide a balanced and integrated approach to this multi-disciplinary STD CRC program. The targeted population is Mexican-American women and the already established and ongoing community activities and collaborations that focus on the health care of this patient group offer a unique aspect of our application. At the basic science level we emphasize 3 infectious agents (Trichomonas vaginalis, Treponema pallidum and herpes simplex virus) and interrelate these projects with the other components of the CRC. Project 1 will dissect the molecular mechanisms by which trichomonads regulate important immunogenic surface proteins and how this influences disease pathogenesis. Project 2 concentrates on the interaction between T. pallidum and specific host macromolecules and proposes strategies to further characterize the surface membrane of virulent treponemes so that the complex pathobiology associated with this spirochete can be clarified. Project 3 examines the replication and transactivation properties of specific HSV isolates and relates these data with the extent of disease and recurrence of HSV infection, as well as, other viral STD such as HIV and human papilloma virus. Project 4 identifies behavioral and motivational patterns of the targeted Mexican-American women population that represents the key patient group in the CRC. This component is a pivotal link with the basic, clinical and outreach activities of the CRC. Project 5 concentrates on the role of primary health care professionals as resources in educating patient populations about the transmission and prevention of STD and will closely interact with the four other projects and related cores. Five cores have been established (Administrative, Biotechnology, Clinical, Statistical and Developmental), and these cores play key roles in the coordination of the CRC projects.